Donald Trump has repeatedly said during his campaign to return to the presidency of the United States that he could quickly negotiate an end to the Russian war in Ukraine. Ukraine and its allies now fear that once Trump is inaugurated in January, the United States will abandon support for efforts to reverse the Russian invasion.

Officials on the eastern flank of the North Atlantic Treaty Organization (NATO) are particularly concerned that if Ukraine is weakened to the point of having to agree to cede land, it will embolden Russian President Vladimir Putin and other leaders with territorial ambitions.

What did Trump say about the war in Ukraine?

In a September presidential debateTrump sidestepped the question of whether he wanted Ukraine to succeed in expelling the Russian invaders.

Instead, he repeatedly said during the campaign that the fighting must stop and that he could end the war “in a day” through a settlement.

His vice-presidential running mate, JD Vance, said in a September interview that a deal would “probably” involve Russia retaining land it has seized in Ukraine and Ukraine agreeing to give up its goal of NATO membership.

Such a vision of ending the war is a far cry from that of Ukrainian President Volodymyr Zelenskyy, who said his country could not accept a frozen conflict or an exchange of territory for peace.

Trump has complained about the extent of U.S. support for Ukraine without explicitly threatening to end it. But some fear he will use the aid as leverage to get Ukraine to make concessions to Russia to end the war.